見つけました。 TCPストリームをFllowingすることは私に次を与えた:
GET/HTTP/1.1
Host: 10.0.0.138
Connection: keep-alive
Cache-Control: max-age=0
Authorization: Basic UG90YXRvOg==
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8,he;q=0.6
HTTP/1.0 401 Unauthorized
WWW-Authenticate: Basic realm="NETGEAR DGN2200v2BEZEQ"
Content-type: text/html
<html>
<head><title>401 Unauthorized</title></head>
<body><h1>401 Unauthorized</h1>
<p>Access to this resource is denied, your client has not supplied the correct authentication.</p></body>
</html>
ユーザ名とパスワードがusername:password
の形式でbase64
でエンコードされています。